Hello all! I want to find a disc brake posi rear end to swap into my 92 RS
Im thinking a fourth gen rear would be easier to find at the junkyard
Does anyone know off hand if the axle ratio is in the vin or rpo?
What digit would it be if it is there?
Im thinking it would be much easier to just be able to look at the vin or sticker on the cars out there to find what I want before I pull it lol

 

For the 4th gens here is a list of the RPO codes. You are mainly concerned with the ones that start with G**, such as G80 (posi) and GU* (gear ratio).

4th gen RPO Codes

 

I just pop the cover and look at the numbers on the ring gear and divide them to get the gear ratio. This allows me to inspect the gears, see the condition of the gear oil, and look for metal shavings/metal chunks.

 

I think v6 cars Had better gearing. brakes are the same tho

 

I wouldn't spend several hundred dollars on a rear without inspecting the internals. Check the following link for the "numbers" that supr mentions (The RPO's only indicate what was in the car from the factory; they don't necessarily reflect what might have been transplanted after the fact--see the second link):

https://www.thirdgen.org/forums/tran...-10-bolts.html

https://www.thirdgen.org/forums/tran...pain-rear.html

JamesC

 

Oh, and another idea, if you have the time, tools, and abilties is to do the conversion yourself. You already have 28 spline axles and the newer style housing. I would suggest go the the yard and find a posi in any 4th gen and pull that plus the pinion. If you find a 94-97 Z28 rear you will get the posi, PBR disk conversion, and possibly gears in one shot. A 98-02 (any motor w/G80) will net you the better torsen posi. As was stated, the V-6 cars in all gens have better gearing in them. Usually a 3.42